1. Field of the Invention
The present invention relates to a wafer processing method.
2. Description of the Related Art
In recent years, a flip chip mounting method has been widely adopted to reduce the size and thickness of a package. The flip chip mounting method is a method including the steps of forming a plurality of projection electrodes called bumps on the front side of a wafer for flip chip mounting and connecting each chip divided from the wafer through the bumps to a mounting substrate. The front side of the wafer for flip chip mounting is a mount side to be mounted to the mounting substrate, and the back side of the wafer is a grind side to be ground (see Japanese Patent Laid-open No. 2006-229021, for example).
As a method for dividing the wafer into the individual chips, there is a method including the steps of attaching the wafer to an adhesive tape supported to an annular frame, applying a laser beam to the wafer along a plurality of division lines to thereby form a modified layer inside the wafer along each division line, and expanding the adhesive tape to thereby divide the wafer into the individual chips along each division line where the modified layer is formed as a break start point (see Japanese Patent Laid-open No. 2009-277778, for example).